Answer:
69.7173 u
Explanation:
The abundance of the first isotope is =60.40%
So the abundance of the second isotope =100%-60.40%=39.6%
Atomic mass of first isotope = 68.9257
So the average atomic mass of the first isotope =68.9257×0.6040=41.6311 u
Atomic mass of the second isotope =70.9249 u
So average atomic mass of second isotope =70.9249×0.396=28.086
Now the average atomic mass =41.6311+28.086=69.7173 u
Answer:
The acceleration of the object is 20 meters per second square = 20 m/s^2
Explanation:
Recall that acceleration is defined as the change in velocity divided the time it takes for the change. Therefore , if the object accelerates from rest (zero velocity) to 70 m/s , the change in velocity is (70 m/s - 0 m/s = 70 m/s)
which divided by the 3.5 seconds it took for the change, gives:
acceleration = (70 m/s / 3.5 s ) = 20 m/s^2
